1 #ifndef __LINUX_BITMAP_H 2 #define __LINUX_BITMAP_H 3 4 #ifndef __ASSEMBLY__ 5 6 #include <linux/types.h> 7 #include <linux/bitops.h> 8 #include <linux/string.h> 9 #include <linux/kernel.h> 10 11 /* 12 * bitmaps provide bit arrays that consume one or more unsigned 13 * longs. The bitmap interface and available operations are listed 14 * here, in bitmap.h 15 * 16 * Function implementations generic to all architectures are in 17 * lib/bitmap.c. Functions implementations that are architecture 18 * specific are in various include/asm-<arch>/bitops.h headers 19 * and other arch/<arch> specific files. 20 * 21 * See lib/bitmap.c for more details. 22 */ 23 24 /* 25 * The available bitmap operations and their rough meaning in the 26 * case that the bitmap is a single unsigned long are thus: 27 * 28 * Note that nbits should be always a compile time evaluable constant. 29 * Otherwise many inlines will generate horrible code. 30 * 31 * bitmap_zero(dst, nbits) *dst = 0UL 32 * bitmap_fill(dst, nbits) *dst = ~0UL 33 * bitmap_copy(dst, src, nbits) *dst = *src 34 * bitmap_and(dst, src1, src2, nbits) *dst = *src1 & *src2 35 * bitmap_or(dst, src1, src2, nbits) *dst = *src1 | *src2 36 * bitmap_xor(dst, src1, src2, nbits) *dst = *src1 ^ *src2 37 * bitmap_andnot(dst, src1, src2, nbits) *dst = *src1 & ~(*src2) 38 * bitmap_complement(dst, src, nbits) *dst = ~(*src) 39 * bitmap_equal(src1, src2, nbits) Are *src1 and *src2 equal? 40 * bitmap_intersects(src1, src2, nbits) Do *src1 and *src2 overlap? 41 * bitmap_subset(src1, src2, nbits) Is *src1 a subset of *src2? 42 * bitmap_empty(src, nbits) Are all bits zero in *src? 43 * bitmap_full(src, nbits) Are all bits set in *src? 44 * bitmap_weight(src, nbits) Hamming Weight: number set bits 45 * bitmap_set(dst, pos, nbits) Set specified bit area 46 * bitmap_clear(dst, pos, nbits) Clear specified bit area 47 * bitmap_find_next_zero_area(buf, len, pos, n, mask) Find bit free area 48 * bitmap_find_next_zero_area_off(buf, len, pos, n, mask) as above 49 * bitmap_shift_right(dst, src, n, nbits) *dst = *src >> n 50 * bitmap_shift_left(dst, src, n, nbits) *dst = *src << n 51 * bitmap_remap(dst, src, old, new, nbits) *dst = map(old, new)(src) 52 * bitmap_bitremap(oldbit, old, new, nbits) newbit = map(old, new)(oldbit) 53 * bitmap_onto(dst, orig, relmap, nbits) *dst = orig relative to relmap 54 * bitmap_fold(dst, orig, sz, nbits) dst bits = orig bits mod sz 55 * bitmap_parse(buf, buflen, dst, nbits) Parse bitmap dst from kernel buf 56 * bitmap_parse_user(ubuf, ulen, dst, nbits) Parse bitmap dst from user buf 57 * bitmap_parselist(buf, dst, nbits) Parse bitmap dst from kernel buf 58 * bitmap_parselist_user(buf, dst, nbits) Parse bitmap dst from user buf 59 * bitmap_find_free_region(bitmap, bits, order) Find and allocate bit region 60 * bitmap_release_region(bitmap, pos, order) Free specified bit region 61 * bitmap_allocate_region(bitmap, pos, order) Allocate specified bit region 62 */ 63 64 /* 65 * Also the following operations in asm/bitops.h apply to bitmaps. 66 * 67 * set_bit(bit, addr) *addr |= bit 68 * clear_bit(bit, addr) *addr &= ~bit 69 * change_bit(bit, addr) *addr ^= bit 70 * test_bit(bit, addr) Is bit set in *addr? 71 * test_and_set_bit(bit, addr) Set bit and return old value 72 * test_and_clear_bit(bit, addr) Clear bit and return old value 73 * test_and_change_bit(bit, addr) Change bit and return old value 74 * find_first_zero_bit(addr, nbits) Position first zero bit in *addr 75 * find_first_bit(addr, nbits) Position first set bit in *addr 76 * find_next_zero_bit(addr, nbits, bit) Position next zero bit in *addr >= bit 77 * find_next_bit(addr, nbits, bit) Position next set bit in *addr >= bit 78 */ 79 80 /* 81 * The DECLARE_BITMAP(name,bits) macro, in linux/types.h, can be used 82 * to declare an array named 'name' of just enough unsigned longs to 83 * contain all bit positions from 0 to 'bits' - 1. 84 */ 85 86 /* 87 * lib/bitmap.c provides these functions: 88 */ 89 90 extern int __bitmap_empty(const unsigned long *bitmap, unsigned int nbits); 91 extern int __bitmap_full(const unsigned long *bitmap, unsigned int nbits); 92 extern int __bitmap_equal(const unsigned long *bitmap1, 93 const unsigned long *bitmap2, unsigned int nbits); 94 extern void __bitmap_complement(unsigned long *dst, const unsigned long *src, 95 unsigned int nbits); 96 extern void __bitmap_shift_right(unsigned long *dst, const unsigned long *src, 97 unsigned int shift, unsigned int nbits); 98 extern void __bitmap_shift_left(unsigned long *dst, const unsigned long *src, 99 unsigned int shift, unsigned int nbits); 100 extern int __bitmap_and(unsigned long *dst, const unsigned long *bitmap1, 101 const unsigned long *bitmap2, unsigned int nbits); 102 extern void __bitmap_or(unsigned long *dst, const unsigned long *bitmap1, 103 const unsigned long *bitmap2, unsigned int nbits); 104 extern void __bitmap_xor(unsigned long *dst, const unsigned long *bitmap1, 105 const unsigned long *bitmap2, unsigned int nbits); 106 extern int __bitmap_andnot(unsigned long *dst, const unsigned long *bitmap1, 107 const unsigned long *bitmap2, unsigned int nbits); 108 extern int __bitmap_intersects(const unsigned long *bitmap1, 109 const unsigned long *bitmap2, unsigned int nbits); 110 extern int __bitmap_subset(const unsigned long *bitmap1, 111 const unsigned long *bitmap2, unsigned int nbits); 112 extern int __bitmap_weight(const unsigned long *bitmap, unsigned int nbits); 113 114 extern void bitmap_set(unsigned long *map, unsigned int start, int len); 115 extern void bitmap_clear(unsigned long *map, unsigned int start, int len); 116 117 extern unsigned long bitmap_find_next_zero_area_off(unsigned long *map, 118 unsigned long size, 119 unsigned long start, 120 unsigned int nr, 121 unsigned long align_mask, 122 unsigned long align_offset); 123 124 /** 125 * bitmap_find_next_zero_area - find a contiguous aligned zero area 126 * @map: The address to base the search on 127 * @size: The bitmap size in bits 128 * @start: The bitnumber to start searching at 129 * @nr: The number of zeroed bits we're looking for 130 * @align_mask: Alignment mask for zero area 131 * 132 * The @align_mask should be one less than a power of 2; the effect is that 133 * the bit offset of all zero areas this function finds is multiples of that 134 * power of 2. A @align_mask of 0 means no alignment is required. 135 */ 136 static inline unsigned long 137 bitmap_find_next_zero_area(unsigned long *map, 138 unsigned long size, 139 unsigned long start, 140 unsigned int nr, 141 unsigned long align_mask) 142 { 143 return bitmap_find_next_zero_area_off(map, size, start, nr, 144 align_mask, 0); 145 } 146 147 extern int __bitmap_parse(const char *buf, unsigned int buflen, int is_user, 148 unsigned long *dst, int nbits); 149 extern int bitmap_parse_user(const char __user *ubuf, unsigned int ulen, 150 unsigned long *dst, int nbits); 151 extern int bitmap_parselist(const char *buf, unsigned long *maskp, 152 int nmaskbits); 153 extern int bitmap_parselist_user(const char __user *ubuf, unsigned int ulen, 154 unsigned long *dst, int nbits); 155 extern void bitmap_remap(unsigned long *dst, const unsigned long *src, 156 const unsigned long *old, const unsigned long *new, unsigned int nbits); 157 extern int bitmap_bitremap(int oldbit, 158 const unsigned long *old, const unsigned long *new, int bits); 159 extern void bitmap_onto(unsigned long *dst, const unsigned long *orig, 160 const unsigned long *relmap, unsigned int bits); 161 extern void bitmap_fold(unsigned long *dst, const unsigned long *orig, 162 unsigned int sz, unsigned int nbits); 163 extern int bitmap_find_free_region(unsigned long *bitmap, unsigned int bits, int order); 164 extern void bitmap_release_region(unsigned long *bitmap, unsigned int pos, int order); 165 extern int bitmap_allocate_region(unsigned long *bitmap, unsigned int pos, int order); 166 #ifdef __BIG_ENDIAN 167 extern void bitmap_copy_le(unsigned long *dst, const unsigned long *src, unsigned int nbits); 168 #else 169 #define bitmap_copy_le bitmap_copy 170 #endif 171 extern unsigned int bitmap_ord_to_pos(const unsigned long *bitmap, unsigned int ord, unsigned int nbits); 172 extern int bitmap_print_to_pagebuf(bool list, char *buf, 173 const unsigned long *maskp, int nmaskbits); 174 175 #define BITMAP_FIRST_WORD_MASK(start) (~0UL << ((start) & (BITS_PER_LONG - 1))) 176 #define BITMAP_LAST_WORD_MASK(nbits) (~0UL >> (-(nbits) & (BITS_PER_LONG - 1))) 177 178 #define small_const_nbits(nbits) \ 179 (__builtin_constant_p(nbits) && (nbits) <= BITS_PER_LONG) 180 181 static inline void bitmap_zero(unsigned long *dst, unsigned int nbits) 182 { 183 if (small_const_nbits(nbits)) 184 *dst = 0UL; 185 else { 186 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 187 memset(dst, 0, len); 188 } 189 } 190 191 static inline void bitmap_fill(unsigned long *dst, unsigned int nbits) 192 { 193 unsigned int nlongs = BITS_TO_LONGS(nbits); 194 if (!small_const_nbits(nbits)) { 195 unsigned int len = (nlongs - 1) * sizeof(unsigned long); 196 memset(dst, 0xff, len); 197 } 198 dst[nlongs - 1] = BITMAP_LAST_WORD_MASK(nbits); 199 } 200 201 static inline void bitmap_copy(unsigned long *dst, const unsigned long *src, 202 unsigned int nbits) 203 { 204 if (small_const_nbits(nbits)) 205 *dst = *src; 206 else { 207 unsigned int len = BITS_TO_LONGS(nbits) * sizeof(unsigned long); 208 memcpy(dst, src, len); 209 } 210 } 211 212 static inline int bitmap_and(unsigned long *dst, const unsigned long *src1, 213 const unsigned long *src2, unsigned int nbits) 214 { 215 if (small_const_nbits(nbits)) 216 return (*dst = *src1 & *src2 & BITMAP_LAST_WORD_MASK(nbits)) != 0; 217 return __bitmap_and(dst, src1, src2, nbits); 218 } 219 220 static inline void bitmap_or(unsigned long *dst, const unsigned long *src1, 221 const unsigned long *src2, unsigned int nbits) 222 { 223 if (small_const_nbits(nbits)) 224 *dst = *src1 | *src2; 225 else 226 __bitmap_or(dst, src1, src2, nbits); 227 } 228 229 static inline void bitmap_xor(unsigned long *dst, const unsigned long *src1, 230 const unsigned long *src2, unsigned int nbits) 231 { 232 if (small_const_nbits(nbits)) 233 *dst = *src1 ^ *src2; 234 else 235 __bitmap_xor(dst, src1, src2, nbits); 236 } 237 238 static inline int bitmap_andnot(unsigned long *dst, const unsigned long *src1, 239 const unsigned long *src2, unsigned int nbits) 240 { 241 if (small_const_nbits(nbits)) 242 return (*dst = *src1 & ~(*src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; 243 return __bitmap_andnot(dst, src1, src2, nbits); 244 } 245 246 static inline void bitmap_complement(unsigned long *dst, const unsigned long *src, 247 unsigned int nbits) 248 { 249 if (small_const_nbits(nbits)) 250 *dst = ~(*src); 251 else 252 __bitmap_complement(dst, src, nbits); 253 } 254 255 static inline int bitmap_equal(const unsigned long *src1, 256 const unsigned long *src2, unsigned int nbits) 257 { 258 if (small_const_nbits(nbits)) 259 return ! ((*src1 ^ *src2) & BITMAP_LAST_WORD_MASK(nbits)); 260 else 261 return __bitmap_equal(src1, src2, nbits); 262 } 263 264 static inline int bitmap_intersects(const unsigned long *src1, 265 const unsigned long *src2, unsigned int nbits) 266 { 267 if (small_const_nbits(nbits)) 268 return ((*src1 & *src2) & BITMAP_LAST_WORD_MASK(nbits)) != 0; 269 else 270 return __bitmap_intersects(src1, src2, nbits); 271 } 272 273 static inline int bitmap_subset(const unsigned long *src1, 274 const unsigned long *src2, unsigned int nbits) 275 { 276 if (small_const_nbits(nbits)) 277 return ! ((*src1 & ~(*src2)) & BITMAP_LAST_WORD_MASK(nbits)); 278 else 279 return __bitmap_subset(src1, src2, nbits); 280 } 281 282 static inline int bitmap_empty(const unsigned long *src, unsigned nbits) 283 { 284 if (small_const_nbits(nbits)) 285 return ! (*src & BITMAP_LAST_WORD_MASK(nbits)); 286 287 return find_first_bit(src, nbits) == nbits; 288 } 289 290 static inline int bitmap_full(const unsigned long *src, unsigned int nbits) 291 { 292 if (small_const_nbits(nbits)) 293 return ! (~(*src) & BITMAP_LAST_WORD_MASK(nbits)); 294 295 return find_first_zero_bit(src, nbits) == nbits; 296 } 297 298 static inline int bitmap_weight(const unsigned long *src, unsigned int nbits) 299 { 300 if (small_const_nbits(nbits)) 301 return hweight_long(*src & BITMAP_LAST_WORD_MASK(nbits)); 302 return __bitmap_weight(src, nbits); 303 } 304 305 static inline void bitmap_shift_right(unsigned long *dst, const unsigned long *src, 306 unsigned int shift, int nbits) 307 { 308 if (small_const_nbits(nbits)) 309 *dst = (*src & BITMAP_LAST_WORD_MASK(nbits)) >> shift; 310 else 311 __bitmap_shift_right(dst, src, shift, nbits); 312 } 313 314 static inline void bitmap_shift_left(unsigned long *dst, const unsigned long *src, 315 unsigned int shift, unsigned int nbits) 316 { 317 if (small_const_nbits(nbits)) 318 *dst = (*src << shift) & BITMAP_LAST_WORD_MASK(nbits); 319 else 320 __bitmap_shift_left(dst, src, shift, nbits); 321 } 322 323 static inline int bitmap_parse(const char *buf, unsigned int buflen, 324 unsigned long *maskp, int nmaskbits) 325 { 326 return __bitmap_parse(buf, buflen, 0, maskp, nmaskbits); 327 } 328 329 #endif /* __ASSEMBLY__ */ 330 331 #endif /* __LINUX_BITMAP_H */ 332